A heat pump hot water supply device heats a refrigerant by absorbing heat from the atmosphere and compressing the refrigerant using electricity. The heat is then transferred to the water via a heat exchanger, creating hot water. The heat pump hot water supply device uses less energy than a conventional electric hot water heater. Moreover, the heat pump heating device is an energy saving heating device that uses water heated by the heat pump for the heater.
For example, Patent Literature (PTL) 1 discloses an arrangement for a low cost supply of power by a power company (hot time 22). Customers participating in this arrangement can use power under a fee structure that is cheaper than the usual rate in exchange for their power being cut off during a peak power consumption time period (for example, 19:00 to 22:00). Moreover, this arrangement is beneficial to the power company as well since the supply of power during the peak time period can be reduced and equalized.